Electrical socket contacts



1951 s. 'r. DEAKIN 3,012,221

ELECTRICAL SOCKET CONTACTS Filed Oct. 11, 1957 1 (Pb 53 5') nuuuu United States Patent 3,012,221 ELECTRICAL SOCKET CONTACTS Stanley Thomas Deakin, Ewell West, Surrey, England, assignor to Siemens Edison Swan Limited, London, England, a British company Filed Oct. 11, 1957, Ser. No. 689,589 Claims. (Cl. 339-258) This invention relates to electrical socket contacts of the kind comprising a pair of resilient prongs adapted to detachably engage opposite sides of electrical contact pins and has important application in socket contact assemblies for receiving multi-pin electrical connectors, plugs, thermionic valves and the like.

The resilient prongs of such contacts are so arranged that when a contact pin is pushed between them they will press against the pin with a good electrical connection while at the same time permit ready disengagement of the pin.

It is an object of the present invention to provide an improved electrical socket contact which is easy to manufacture and offers a high degree of resilience to a pin inserted between the prongs of the contact.

Accordingly the present invention provides a socket contact formed of sheet metal and comprising a pair of prongs and a tag portion extending from the root end of the prongs, the prongs being twisted in the same angular direction about parallel longitudinal axes and the laterally extending bends formed by the twisting operation having varying radii of curvature, the radius of curvature of each prong being greatest at the inner edge, i.e. adjacent the line of separation of the prong and decreasing progressively to the outer edge so that the free ends of the prongs overlie each other and wherein said free ends are extended together laterally of their longitudinal axes so as to form a pair of feet adapted to resiliently contact opposite sides of an electrical contact pin when inserted between them.

Preferably the feet extend in a direction parallel to the plane of the sheet from which the contact is formed.

It is desirable to swage or bend the entry edge of the feet to assist entry of a pin between them. It is possible to arrange for an entry of a pin into a socket contact either forwardly or by a sideways motion. Furthermore, the pins when inserted may lie either in a direction generally transverse of the longitudinal axes of the prongs or else parallel to them. The entry edges of the feet can thus either be the side edges which extend parallel to said longitudinal axes, or else those edges perpendicular to the longitudinal axes of the prongs.

The tag portion of the contact may be formed so that V the end portion thereof extends perpendicularly to the prongs and may be in the opposite direction to the feet of the prongs. The plane of the end portion may be bent so as to lie at right angles to the plane of the remainder of the socket so as to form a shoulder which assists in locating the socket in a holder.

A plurality of such socket contacts may be secured to an insulating body portion so as to form a socket contact assembly adapted to receive a multi-pin electrical connector or other electrical component, the contacts being positioned to receive associated pins of the connectors so that the pins lie between their feet.

In order that the invention may be more fully understood' reference will now be made to the accompanying drawing in which FIG. 1 shows a socket contact in accordance with the invention and FIGS. 2 and 3 show two contact assemblies each embodying the invention.

Referring to FIG. 1 there is shown therein a socket contact 1 formed from a sheet metal blank comprising a pair of prongs or legs 2 and 3 diverging like the arms of a V. and a tag portion 4 extending from the root end of the prongs. The free ends 9 and 10 of the prongs are provided with feet 11 and 12 which extend laterally on the same side of the prongs. The prongs are each twisted about parallel axes extending longitudinally of the prongs and are contoured so as to be wrapped partially round oblique cones having their bases at the inner edges of the prongs and their apexes at the outer edges of the prongs. The lateral bends 5 and 6 produced thereby in each prong have a varying radius of curvature across the width of the prong. The twisting action causes the radius of curvature of each bend to be greatest as the inner edge 7 of prong 2 i.e. adjacent the line of separation of the prongs and to decrease transversely towards the outer edge 8 of a prong. The bend produced in prong 3 is of similar shape.

By this means the free ends 9 and 10 of the prongs overlie each other and the feet 11 and 12 resiliently contact opposite sides of an electrical connection pin lying between them. It can be seen that the lateral bends in the prongs can be readily manufactured and the effect of these bends is to produce a high degree of resilience in each prong when they are forced apart by insertion of a pin between them.

As shown in the figure the side edges 13 and 14 of the feet are swaged or bent to assist insertion of a pin either forwardly or sideways in a direction transversely of the longitudinal axes of the prongs.

The tag portion of the contact comprises an intermediate portion 17 and an end portion 18, which end portion extends perpendicularly to the prongs and parallel and in opposite direction to the feet of the prongs so that the electrical connection may readily be made to said end portion without interfering the plug-in action of the pin. Conveniently a right angle bend 19 may be provided between the intermediate and end portions of the prongs so as to form a shoulder 20 for assisting in location of the contact in an assembly.

Referring now to FIG. 2 there is shown a contact assembly comprising a plurality of socket contacts 1 similar to that described with reference to FIG. 1. These socket contacts are secured to an insulating body portion 21 which is mounted in a frame 22 adapted to be fixed to an electronic equipment chassis or the like. Socket contacts 1 are positioned to receive the correspondingly positioned pins of an electrical multi-pin component, such as a plug, by a forward motion of the pins so that the pins lie between the feet of the contacts. It will be seen that in the socket contact assembly shown the pins when inserted will extend generally transversely of the axis of the prongs. It will be appreciated that by providing an intermediate portion 17 in each contact it is possible to allow for errors and wide tolerances in the spacing of the pins of a plug since the intermediate portion 17 can be resiliently deflected by the action of inserting a pin into a socket contact.

Referring now to FIG. 3 there is shown therein a socket contact assembly suitable for one type of valve having pin connectors at either end thereof. Each contact 1 is secured in an associated slot 25 cut in the insulating body portion 26 of the assembly, and to assist in proper location of a contact in this associated slot, the shoulder 20 formed in the end portion of the contact is located in a recess 27 formed in the end face of the assembly body. Means will also be provided for preventing movement of the contact in the slot. The valve is inserted by a sideways motion of the pins laterally of the prongs so that when inserted the pins will lie between the feet of the contacts and extend parallel to the prongs.

I What I claim is:

l. A resilient terminal clip of sheet metal formed from a flat blank comprising a tag portion having a bifurcated portion extending therefrom forming two legs the free end of each 'of which includes a foot portion extending transversely therefrom, each leg being twisted toward each other providing a contoured portion at the joining 'area of each leg with the tag portion so that the feet overlie each other and the feet extend in the same cli- -r'ection from the respective legs for receiving 'a terminal therebetwe'en.

-2. The invention according to claim 1 wherein said contoured portion is substantially conical.

3. The invention according to claim 1 wherein said contoured,portion'comprises a bent portion.

4. A resilient terminal-clip of sheet metal formed from a flat blank comprising atag portion having a bifurcated portion extending therefrom forming two legs the free end of each of which includes'a foot portion extending transversely therefrom, each leg being twisted toward each other providing a contoured portion at the joining area of each leg with the tag portion so that the feet overlie each other in spaced relation and the feet extend in the same direction from the respective legs for receiving a terminal therebetween, so that members inserted 4 in the terminal clip lie between the feet in a direction generally transverse of the longitudinal axes of the legs, 5. A resilient terminal clip of sheet metal formed from a fiat blank comprising a tag portion having a bifurcated portion extending therefrom forming two legs the free end of each of which includes a foot portion extending transversely therefrom, each leg being twisted toward each other providing a contoured portion at the joining area of each leg with the tag ,portion so that the feet overlie each other in spaced relation and the feet extend in the same direction from the respective legs for receiving a terminal therebetween, so that members inserted in the terminal clip lie between the feet in a direction generally parallel to the longitudinal axes of the prongs.

References Cited in the file of this patent UNITED STATES PATENTS 7 Australia -Q. Feb. 20, 1940 

